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Discussion Starter · #1 ·
Couple weeks ago I posted problems I'm having with Red with most telling me to rebuild the carb which I just finished doing. Same exact problem(s).

Re-cap:

Edelbrock 1404 carb with electric choke. The engine use to fire right up after I set the choke with no hesitation. Now upon cold start, it cranks and cranks. Sometimes it will fire up but typically it will fireup after I let go of the ignition key.

The typical cold start high idle is not consistant running at 1500 rpms. Now it fires up and cold idles at say 800-900rpm.

Gas backfiring up through carb-This am during initial crank after I let go of the key it attempted to fire up but I saw and smelled gas vapor shooting up through the carb.

Took the car for a good drive to visit someone. Car sat for about 40 minutes. Upon startup it acted like today's cold start with vapor shooting up through the carb and air filter. 2nd start up, it fired right up.

Once running, if I shut it off and fire it right up, it ignites immediately. Wait 30-40 minutes it becomes harder to start.

Yes, it's very possible I did not rebuild the carb correctly. It was extremely clean inside when I tore it apart and the symptoms are the same now as they were before the rebuild.

Can it be electrical? Why does it fireup when I let go of the key? Yes, I did replace the switch thinking that was the culprit.

Happy 2008 }:|
 

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cmayna said:
Now upon cold start, it cranks and cranks. Sometimes it will fire up but typically it will fireup after I let go of the ignition key.


Can it be electrical? Why does it fireup when I let go of the key? Yes, I did replace the switch thinking that was the culprit.

Happy 2008 }:|
Is there an adjustment for the ignition switch? From your description, it sounds as though the switch is out of adjustment and you are only getting contact when you release the key.
 

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There's a connection on the starter solenoid that directs 12V to the coil while cranking. When you let go of the key, it switches back to ballast voltage. You might want to check that.

Evan.
 

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My problem with cold start is all the gas is gone out of my 4300D carb (even when just installed rebuilt by Pony Carbs). It takes some time for the fuel pump to refill the volume required. There will be one squirt available from the accelerator pump, but no more after that until it fills up.

The difference in idle is probably due to the cam on the choke. I don't know your brand for sure, but there is probably a stop on the linkage that keeps the butterfly valve from completely closing while the choke is engaged.

Good Luck!
Happy New Year.
 

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Discussion Starter · #6 ·
Yes, Duraspark. When testing the voltage during crank vs idle you connect the volt meter to the S terminal of the solenoid and - or + of the battery?

With Duraspark I do not have a wire directly from the solenoid to the + of coil instead I have a bypass wire that connects to that I wire on the solenoid and runs through a ballast resistor and then to the + of the coil. Here's a schematics of my setup, look at the bottom part of the pic.

Need to do a couple errands. Back later to continue with the saga.


 

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I would say to first check both wires for the power feed to the coil. Then, the vapors/gas spitting out of the carb sounds like a slight timing problem. Not sure on you dist. setup but if points, check there. If electronic, make sure no dirt/moisture is in the cap area. Make sure the elec. setup is still tight. Starting immediately when warm could be due to any of the above. The heat can change the wire connections, makes it easier to fire when warm, and clear out moisture problems.

Have you actually looked down the carb (use a mirror) while on cold idle to see if it is flooding?

Does the car run the same as always now and how is the gas consumption?

Maybe Red is jealous of Shag getting more attention. lol
 

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Discussion Starter · #9 ·
How do you check the solenoid? Touch the S terminal and ground? or + of battery?
 

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Discussion Starter · #11 ·
Hmmmmmmmm. I have an extra one, why not swap and see what happens?
 

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I'm betting on the fuel leaking from the bowl while the car sits. Fuel leaks into intake manifold. When cold the fuel has evaporated. When hot it's pooled there making it hard to start.
 

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That's my bet too. My 67 was doing the same thing. I ended up taking the 4V holley off and putting the orginal 2V intake a carb back on. solved my problem.

When you rebuilt the carb, did you use a good kit with good quality gaskets?

Dave
 

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I concur also, float bowl leaking fuel out, sometimes caused by the valve sticking. The only weird thing is the running when the key is turned back off. Other than that (electrical gremlins) I'd wonder if the choke is working properly. I missed all the other posts so I don't know if you've tried hot-wiring to bypass your switch.
 

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Discussion Starter · #15 ·
I replaced the voltage regulator tonight and haven't tried a hot start yet. Will probably wait and do a cold start tomorrow.

If it isn't resolved, I'm considering getting another carb. I used a Edelbrock rebuild kit.

I was told to first start up the engine to warm temp to ensure full bowls in the carb. Then, remove the carb, avoiding tipping and spilling gas out of it and support it above say cardboard to see if the carb leaks. I did so and it never leaked.
 

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Discussion Starter · #16 ·
How does the choke affect warm starts?
 

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Should have no affect on a warm start, assuming that it's adjusted properly. Meaning that the the butterfly valve should be all the way open and off the high speed cam.
Dave
 

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From your diagram,
Check for 12 volts at the I term on the sol while cranking. volt/ohm meter neg to grnd and pos to I term.

if you have a full 12 volts at sol I term,check for 12volts at white wire of ign box when cranking. yes? move to test red wire leaving ign box while cranking it should have 12 volts.
No replace box. loss of voltage to coil when cranking.
 

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I'm not familiar with your carb but I've never seen any carb where the bowels aren't full when cold. I always just take the top off when cold and look for fuel or on Holley style remove the sides. A hot engine could catch fire so I'd be wary of making Red "too" red. To me if you start the engine the pump would always fill the bowels. I would be looking to see if the fuel leaked out when it sits resulting in no start and a vapor build-up if the leakage occurs after drive. Replacing the carb with a known good carb as you plan will take the carb out of the equation.
 

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Are you sure that the electric choke is operating properly (i.e. have you checked the wires/made visual confirmation that choke is closing when cold)? That is certainly where I would start if I had cold starting problems.
 
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